|Publication number||US7147088 B2|
|Application number||US 11/158,984|
|Publication date||Dec 12, 2006|
|Filing date||Jun 23, 2005|
|Priority date||Oct 1, 2002|
|Also published as||CA2501290A1, CA2501290C, EP1549864A2, EP1549864A4, US20030070894, US20050252742, US20060034959, WO2004030987A2, WO2004030987A3|
|Publication number||11158984, 158984, US 7147088 B2, US 7147088B2, US-B2-7147088, US7147088 B2, US7147088B2|
|Inventors||John D. Reid, John R. Rohde, Dean L. Sicking|
|Original Assignee||Reid John D, Rohde John R, Sicking Dean L|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (17), Referenced by (22), Classifications (11), Legal Events (3)|
|External Links: USPTO, USPTO Assignment, Espacenet|
This is a continuation application based upon co-pending U.S. patent application Ser. No. 10/262,366, filed Oct. 1, 2002.
This invention was made in part during work supported by a grant/contract Contract No. DTR557-98-C from DOT/RSPA/Volpe National Transportation System Center. The government may have certain rights in this invention.
The present invention relates to a traffic crash attenuation system. More particularly, the present invention relates to a system, method and apparatus for absorbing the kinetic energy from an impacting vehicle in a controlled and safe manner with roadside safety devices such as: guardrails and median barrier end treatments, crash cushions, and truck mounted attenuators. The system provides for the controlled rupturing of a tubular member by a mandrel whereby forces of an impacting vehicle are absorbed. The present inventive system may utilize a rectangular mandrel and a corresponding rectangular tubular member.
U.S. Pat. No. 4,200,310 illustrates an energy absorbing system which utilizes a number of cylindrical energy absorbing members placed in a series-type relationship on a frame mounted to a truck. The system is provided with an alignment or guidance frame. However, there is nothing which teaches any selectively controlling the rupture of the cylindrical members via a single sided-crash cushion The mechanism of energy dissipation is significantly different than that of the present invention.
U.S. Pat. No. 3,143,321, teaches the use of a frangible tube for energy dissipation. As with the present invention, the apparatus disclosed in U.S. Pat. No. 3,143,321 uses a mandrel receivable within a tubular member. However, there is no teaching of a means for selectively controlling the rupturing along a length of the tubular member.
A controlled fracture or rupturing mechanism which may be used with the single-sided crash attenuation cushion system of the present invention is based on the concept that, when an over-sized plunger with a tapered surface (mandrel 12) is forced into a thin-wall tubing 14 of the generally same shape, pressure is exerted on the edge of the tubing from the inside, as illustrated in
Although this concept may be used with both brittle materials and ductile materials, brittle materials, such as frangible aluminum, ceramics, or concrete, fragment during the process and produce shrapnel that could pose a hazard to nearby traffic or pedestrians. The use of ductile materials or brittle materials which are appropriately coated so as not to produce shrapnel-like fragments may be used. Ductile materials, such as steel, polymers, or FRP materials with longitudinal reinforcement, tear into a number of longitudinal strips that remain attached to the undeformed portions of the tubular energy absorber.
The amount and rate of energy dissipation can be controlled by varying the shape, size, thickness, and strength of the thin-wall tubing 14 and the number of tubes. The location and required force level of the rupture can be controlled by incorporating stress concentrators on the tubing, using holes 17, slots 18, notches, cuts, scores and strengtheners such as gussets 19, shown in
In addition, the controlled fracturing mechanism can be used in combination with other means of energy dissipation. Energy absorbing materials 40A and 40B (
For end-on impacts, the vehicle will contact the impact plate 132 (
For impacts that are end-on at a large angle, the impacting vehicle will initiate the controlled fracturing/bursting process until the thin-wall tubing is bent out of the way or the mandrel disengages from the thin-wall tubing, and then gate behind the device. Similarly, the impacts on the side of the thin-wall tubing 14 near the end of the device cause the thin-wall tubing will be bent out of the way, allowing the vehicle to gate behind the device. Thus, when struck on the corner, either on the end or the side of the cushion, the energy absorbing mechanism begins to collapse longitudinally providing lateral resistance as it begins to bend out of the way.
For impacts into the side of the thin-wall tubing downstream of the beginning of length-of-need, the thin-wall tubing will act like a barrier and contain and redirect the impacting vehicle. An anchoring mechanism will be necessary to resist the tensile forces acting on the tubing to contain and redirect the vehicle. Note that this requirement of containment and redirection is applicable only for devices that have redirective capability, such as a terminal or a redirective crash cushion.
One particular roadside safety device utilizing the controlled fracture mechanism consists of a few major components, as illustrated in
An impact head/plate 50 is provided. Details of the impact head/plate are shown in
The mandrel 12 is much stronger (having a greater tensile strength, a greater thickness, or greater hardness) than the splitting tube 14 to prevent the mandrel from deforming. The mandrel 12 need not have the same cross-sectional shape as the thin-wall tubing, however, there must be only small clearances between the mandrel and the tubing in order to prevent misalignment. For example, channel or wide flange shapes could be used with rectangular frame rail elements as long as the height and depth of the open sections were close to the same as the clear opening in the tube.
The head 13 of the mandrel 12 is tapered so that only the leading portion of the mandrel head 13 initially will fit into the thin-wall tubing. The mandrel 12 may have stress concentrators, e.g., a particular geometrical shape or raised edges, to control where the thin-wall tubing will fracture. For square or rectangular tubes, the mandrel may have a corresponding square or rectangular shape that flares outward. This type of tube/mandrel combination, as discussed below in relation to
As mentioned previously, the controlled fracture mechanism of the present invention may be used in combination with other forms of energy dissipation. One such design (
For example, a composite tube trailer or truck mounted attenuator may use a crushable composite beam as its primary energy dissipation mechanism. Two typical embodiments of this device are shown in
Another embodiment utilizes controlled fracture frame rail elements in addition to composite tube energy absorbers as shown in
As previously stated, the tube bursting energy absorber works on the principal that the energy associated with the propagation of cracks along the length of a tube can be carefully controlled and utilized to dissipate the energy of an impacting vehicle. This system incorporates a tapered mandrel that is forced inside an energy absorbing tube of slightly smaller dimensions. As the tapered mandrel is forced inside the tube, hoop stresses develop in the energy absorbing tube and these stresses are then used to propagate cracks along the length of the tube. The cracks propagate in front of the mandrel such that there is no direct contact between the mandrel and the crack surfaces, thereby limiting friction. The system's operation is somewhat different when incorporated for round and square energy absorbing tubes.
Although a number of energy absorbing systems utilized collapsing round tubes, none of the prior inventions have incorporated square tubes. The corners of square tubes make these energy absorbers perform much differently than round tubes. Because square tubes have rounded corners, a tapered square mandrel forced inside a square tube will tend to contact the tube only in the vicinity of the corners. Although such a system would eventually produce ruptures in the corners of the tube, the sharp corners of the mandrel would contact the crack surfaces and high friction forces would be generated.
A tube bursting energy absorber may avoid this situation by using a tapered mandrel with bevels at each corner. As shown in
Because there are two crack initiators at each corner, two cracks can start and propagate simultaneously. Normally only one of these two cracks will dominate and the other crack will stop propagating. However, when this occurs, one side of the tube is actually a very shallow channel shape, which tends to dissipate more energy when the cracked walls are curled back. Saw cut manufactured cracks placed in the center of each corner can force the crack to run down the center of the tube corner. Thus, initial manufactured cracks can lower the energy dissipation associated with square tubes to some extent.
The energy dissipation rate for this system may be controlled by a number of factors, including the thickness of the energy absorbing tube, bevel angle on the mandrel, lubrication applied to the inside of the energy absorbing tube, and the material used in the energy absorber. Energy is dissipated by the tube bursting energy absorber through three primary mechanisms: crack propagation, curling of the cracked sections of tube, and friction. Crack propagation energy in a square or rectangular tube is controlled primarily by the type and thickness of the material used in the energy absorbing tube. More ductile and tougher metals have higher strain energy release rates and thus dissipate more energy. Likewise, thicker tubes also absorb more energy in the crack propagation process.
Energy dissipated as the cracked sections of a rectangular tube are curled back is controlled by the taper angle of the mandrel and the thickness of the material. Higher mandrel taper angles decrease the radius of the curled sections of cracked tube and thereby increase the energy dissipated in the bending process. However, lower taper angles do increase friction slightly, thereby offsetting the decreased bending energy to some extent. Tube thickness also affects the energy required to curl the cracked sections of the tube.
Friction is the other major source of energy dissipation. Lubricants placed inside the energy absorbing tube can greatly reduce friction energy. Although conventional lubricants such as grease or oil, and other hydrocarbon compositions, can serve this purpose, other lubricants could include zinc used in the galvanizing process, paints, ceramic composition surfaces, and even rust particles.
Round tubes made from ductile materials, such as low carbon steel, will deform greatly when a tapered mandrel is driven inside. If the energy absorber does not include weakening mechanisms as described by Smith (1975), the tube will expand sufficiently to completely engulf the mandrel. In this case, the forces required to push the mandrel inside the energy absorber rise rapidly and the system is ineffective. Smith teaches that, by using a pattern of slots in the energy absorbing tube, it can be made to deform outwardly away from the mandrel and fold back upon itself. In this situation the energy absorbing forces are controlled, but the cost of producing the large numbers of slots, holes, or other weakening mechanisms is high. As described above, a tube bursting energy absorber may involve propagating cracks along the length of the tube. For round tubes, these cracks must be manufactured in the end or along the side of the tube. The cracks are manufactured by placing small saw cuts at strategic points around the tube or by scoring the surface of the tube along its length.
There are two primary advantages of this system. The first advantage is that small saw cuts and/or shallow surface scores are very inexpensive to produce. The second advantage of this approach is that the cracks propagate in front of the mandrel in a manner to prevent direct contact between the mandrel and the crack tip. By keeping the mandrel out of the crack tip, friction is greatly reduced and the energy dissipation rate is controlled.
Just as in the case with the square tube, the energy dissipation rate of the absorber can be influenced by the thickness of the energy absorbing tube, bevel angle on the mandrel, lubrication applied to the inside of the energy absorbing tube, and the material used in the energy absorber. The primary difference in energy dissipation between round and square tubes is that round tubes can have a number of different crack configurations. The crack propagation energy is directly related to the number of cracks induced in the tube. The energy dissipated as the cracked sections of tube are curled back is controlled by the taper angle of the mandrel and the number of cracks induced in the tube. When more cracks are induced in the tubes, the moment of inertia of each cracked section is reduced. By reducing the section modulus, the energy required to bend each section back is reduced. Energy dissipation by round tubes is also controlled by all of the factors mentioned previously for the square tube.
For any given tube configuration, energy dissipation rates are relatively constant. However, for many safety applications it is desirable to design energy absorbers with multiple energy absorption stages. Another advantage of the tube bursting energy absorber is that multiple stages are easily implemented by nesting energy absorbing tubes of varying lengths. For example, a two-stage energy absorbing system can be set up by inserting a longer tube inside a shorter tube of larger dimension. The first stage would consist of a single tube while the second stage would consist of two nested tubes. When the mandrel reaches the nested tube, cracks will be propagated down both the inner and outer tubes and the energy dissipation increases to a higher level. The energy dissipation rate for the two combined tubes is generally less than the sum of the rate for each tube bursted separately. This decrease can be attributed to reduced friction associated with the combined bursting process.
Another means of developing a two-stage energy absorbing system is to score only the front portion of a tubular section. The scored section of the tube typically has a lower energy dissipation rate than the un-scored portion of the tube, thus forming a two-staged energy absorbing system.
A box-beam burster energy absorbing tube single-sided crash cushion 100 (shown in
The BEAT-SSCC described in
(a) a transition section for direct attachment of the crash cushion to the fixed-object hazard, e.g., end of concrete barrier, that the crash cushion in intended to shield; and
(b) a third stage of energy absorption.
When the crash cushion is impacted end-on by an errant vehicle, the impact head 104 will engage and interlock mechanically with the front of the vehicle. As the vehicle proceeds forward, the impact head will be pushed forward along a box-beam rail element. The impact head will then contact a post breaker beam and break off the end steel breakaway post 1, thus releasing a cable anchorage.
Shortly after breaking the end 1 post, a tapered mandrel will contact the end of the stage one energy absorbing tube 501 and be forced inside the tube. As described above, cracks will then be initiated at the corners of the tube, the locations of which may be controlled by notches cut into the end of the tube. As the vehicle proceeds forward pushing the tapered mandrel into the tube, the cracks will continue to propagate in front of the mandrel until:
(a) the vehicle comes to a controlled and safe stop;
(b) the vehicle safely yaws away and loses contact with the tube/terminal; or
(c) the entire length of the stage one energy absorbing tube is used up.
Upon complete bursting of the stage one energy absorbing tube 501, the process will repeat with the stage two energy absorbing tube 502A until:
(a) the vehicle comes to a controlled and safe stop;
(b) the vehicle safely yaws away and loses contact with the tube/terminal; or
(c) the stage two energy absorbing tube is used up to the beginning of stage three.
Upon reaching the beginning of stage three, bursting of the energy absorbing tube will continue. In addition, a short section of box-beam, which serves as a blockout 504 to posts 7 and 8, and the rigid object (such as a concrete barrier 600) will be pushed forward. The downstream end of this box-beam section 504 will then be pushed into a tapered area between the outer box-beam rail element 652 and the face of the concrete barrier (or other rigid object). This deforms or compresses the downstream end of the box-beam section, which dissipates additional energy. Other methods of dissipating impact energy as the blockout tube is pushed forward are presented below.
For impacts into the side of the crash cushion downstream of the beginning of length-of-need, which is selected to be post 3 or 2.9 m (9 ft. 6 in.) from the end of the crash cushion, the crash cushion will contain and redirect the impacting vehicle. The cable attachment will provide the necessary anchorage to resist the tensile forces acting on the rail element to contain and redirect the vehicle.
The element of the BEAT-SSCC crash cushion 100, shown in
(a) an impact head assembly 104;
(b) a 2.4 m (8 ft.) long section of 152 mm×152 mm×3.2 mm (6 in,×6 in.×⅛ in.) box-beam rail for the stage one energy absorber 501;
(c) a 4.9 m (16 ft., 2½ in.) long section of 152 mm×152 mm×4.8 mm (6 in.×6 in.× 3/16 in.) box-beam rail for the stage two energy absorber 502A;
(d) a fabricated third stage section 502B for attachment to the concrete barrier;
(e) a 1.7 m (5 ft., 6 in.) long section of 152 mm×152 mm×4.8 mm (6 in.×6 in.× 3/16 in.) box-beam blockout rail 504;
(f) a steel breakaway end post 1;
(g) steel breakaway post for posts 2 through 8;
(h) a cable anchorage system 113;
(i) a post breaker 109 attached to the end post 1; and
(j) a restraining cable 117.
The impact head assembly 104 consists of: a front impact plate 132, a mandrel tube 134 that inserts into the energy absorbing tube 501, and a tapered mandrel 138, details of which are shown in the drawing. The front impact plate 132 has a dimension of 510 mm×510 mm (20 in.×20 in.) with 50 mm (2 in.) wide protruded edges to provide a mechanical interlock with the impacting vehicle and to distribute the impact load. The mandrel tube is fabricated from a 1.2 m (46 in.) long section of 114 mm×114 mm×4.8 mm (4.5 in.×4.5 in.× 3/16 in.) tube. The upstream end 139 of the mandrel tube is welded to the back of the impact plate 132. The downstream end of the mandrel tube is inserted into the stage one energy absorbing tube 501 for a distance of approximately 560 mm (22 in.). A tapered end 133 was formed on the downstream end of the mandrel tube 134 by welding 9.5 mm (⅜ in.) thick bent plates to the end, which act like a plunger to shear off bolts at connections to the posts and at splices. Two sets of 12.7 mm (½ in.) thick straps are welded around the mandrel tube to control the clearance of the mandrel tube within the energy absorbing tube, one set near the plunger end (i.e., where the mandrel tube is inserted into the energy absorbing tube) and the second set 135 approximately 560 mm (22 in.) upstream from the plunger end. The cross sectional dimension of the mandrel increases from 114 mm×114 mm (4.5 in.×4.5 in.) to a maximum of 168 mm×168 mm (6.6 in.×6.6 in.). The inside dimension of the energy absorbing tube is 146 mm×146 mm (5.75 in.×5.75 in.).
The stage one energy absorbing tube 501 is a 2.4 m (8 ft.) long section of 152 mm×152 mm×3.2 mm (6 in.×6 in.×⅛ in.) box-beam rail. A cable anchor bracket 700 for one end of the anchor cable 113 is welded to the bottom of the rail. The cable anchor bracket consists of a 12.7 mm (½ in.) thick plate with a 29-mm (1⅛ in.) diameter hole for the cable anchor and reinforced with gussets. Two 63.5 mm×63.5 mm×6.4 mm (2.5 in.×2.5 in.×¼ in.) angles are welded 50 mm (2 in.) upstream from the downstream end of the tube for connection to the standard box-beam rail section. Two special splice plates 750, details of which are shown in the drawing (
The stage two energy absorbing tube 502A is a 4.9 m (16 ft., 2½ in.) long section of 152 mm×152 mm×4.8 mm (6 in.×6 in.× 3/16 in.) box-beam rail. A specially fabricated end section 502B is used to attach the rail elements to the concrete barrier 600. The end section consists of three subsections 650, 652, 654 welded together. The first two sections 650 and 652 are fabricated from 152 mm×152 mm×4.8 mm (6 in.×6 in.× 3/16 in.) box-beam rails, one 1.1 mm (3 ft., 8¼ inc.) long and the other 0.9 m (2 ft., 11⅛ in.) long. The end the first section 650 is welded to the beginning of the second section 652 at an angle of 81 degrees. An end shoe 654 is then welded to the end of the second rail section. The end shoe 654 is bolted to the concrete barrier with 254 mm (10 in.) long 25.4 mm (1 in.) diameter bolts with square washers and nuts. A spacer 658 is placed between the end shoe 654 and the face of the concrete barrier to account for the sloping face of the concrete barrier. The end section 502B is connected to the stage two energy absorbing tube 502A with two other splice plates 760A and 760B, details of which are shown in the drawings (
The stage two energy absorbing tube 502A and the first section 650 of the end section are blocked out from posts 7 and 8 and the concrete barrier 600 with a 1.7 m (5 ft., 6 in.) long 152 mm×152 mm×4.8 mm (6 in.×6 in.× 3/16 in.) box-beam rail. This blockout tube 504 is attached to the stage two energy absorbing tube 502B and the first section 650 of the end section with three sets of 290 mm×89 mm (11½ in.×3½ in.) 6.4 mm (¼ in.) thick straps 660 and 7.9 mm ( 5/16 in.) diameter bolts, one at each end of the blockout tube and one at the end of the concrete barrier.
The blockout tube 504, together with the stage two box-beam rail 502A, provides a stage three energy absorber 502B. First, energy is dissipated by bursting the box-beam tubular section, similar to the stage two energy absorber. Second, energy is dissipated via the following means as the blockout tube is pushed forward:
This stage three energy absorber ends when the mandrel reaches the end of the first section of the end section and/or when the blockout tube can no longer be pushed forward or deformed.
The steel breakaway end post 1 consists of an upper section and a lower section. The section is a 546 mm (21½ in.) long section of standard W 150×13 (W6×9) steel post used with W-beam guardrail systems. The lower section is a 2.4 m (8 ft.) long section of standard W150×13 (W6×25) steel post with a 100 mm (4 in.) wide U-shaped collar welded to the top of the post. The upper post section is bolted to the collar of the lower post using a 10 mm (⅝ in.) diameter Grade 5 bolt. A 32 mm (1¼ in.) wide, 64 mm (2.5 in.) long slot is cut through the web of the upper post section at the bottom to allow attachment of one end of the cable anchor. The box-beam rail 501 is attached to the end post 1 using a special angle support bracket with 7.9 mm ( 5/16 in.) diameter A307 bolts.
Posts 2 through 8 are standard 1.8 m (6 ft.) long breakaway steel posts. For posts 2 through 6 (
A cable anchor assembly 113 (
A post-breaker 109 (
A 6.1 m (20 ft.) long, 6.4 mm (¼ in.) diameter, steel cable 117 is used to retain the impact head in case of a reverse direction impact, similar to the impact conditions under NCHRP test designation 3.39. One end of the cable is attached to the impact head and the other end of the cable is attached to the upstream end of the anchor cable at the end post. The cable is bundled and tied to the impact head to eliminate dangling of the cable.
A front portion from the nose or impact head 104 to post 5, of the BEAT-SSCC is similar to other terminals and crash cushions based on the BEAT technology. The unique features of the BEAT-SSCC from post 5 to the end of the assembly include:
(a) Reduced post spacing of 610 mm (2 ft.) from post 5 through post 8 and 305 mm (1 ft.) from post 8 to the end of the concrete barrier (or fixed object) to stiffen the system so as to minimize the potential for the impacting vehicle to snag on the end of the concrete barrier (or fixed object).
(b) The stage two energy absorbing tube and the first section of the end section are blocked out from posts 7 and 8 and the concrete barrier (or fixed object) with a 1.7 m (5 ft., 6 in.) long 152 mm×152 mm×4.8 mm (6 in.×6 in.× 3/16 in.) box-beam rail. This blockout tube also stiffens the system so as to minimize the potential for the impacting vehicle to snag on the end of the concrete barrier (or fixed object).
(c) The blockout tube, together with the box-beam rail, provides a stage three energy absorber. First, energy is dissipated by bursting the box-beam tubular section, similar to the stage two energy absorber. Second, energy is dissipated via the following means as the blockout tube is pushed forward:
(d) The end section is attached to the concrete barrier (or fixed object) using a specially designed end shoe to minimize the potential for an impacting vehicle snag on the end of the end section when impacted in the reverse direction.
As previously stated, improved splice mechanisms for box-beam guardrails and terminals were developed and successfully crash tested. These splice mechanisms are intended for use with the box-beam Burster Energy Absorbing Terminal (BEAT) applications, but may also be used for any box-beam barrier systems and terminals.
This splice mechanism 950 requires the mandrel to shear off only two bolts at one time, thus greatly reducing the energy and associated force level. Also, the splice plates 750 are outside of the tubes and do not interfere with the mandrel. This splice mechanism 950 was crash tested and shown to perform satisfactorily, meeting all evaluation criteria set forth in NCHRP Report 350 guidelines. The moment capacity of this splice mechanism seems limited by the bolts connecting the splice plates to the angles, rendering the BEAT terminal design more sensitive to redirectional type of impacts.
(a) two bent plate channels 972 welded to the downstream end of the upstream (first) rail element; and
(b) two channel splice plates 974 bolted to the upstream end of the downstream (second) rail element.
The bent plate channels 972 are 517 mm (20⅜ in.) long and 121 mm (4¾ in.) wide, fabricated from 6 mm (¼ in.) thick plates. The height of the channels increases from 48 mm (1⅞ in.) on the downstream (free) end to 51 mm (2 in.) on the upstream (welded) end to provide more clearance for the channel splice plates to slide into place. The channels are welded to the top and bottom of the downstream end of the upstream tube for a length of 152 mm (6 in.). Both ends of the channels are tapered to minimize the potential for snagging by the vehicle.
The channel splice plates 974 are 267 mm (10½ in.) long and fabricated from C102×8 mm (4× 5/16 in.) channels. The channel splice plates are bolted to the top and bottom of the upstream end of the downstream (second) rail element with two 16 mm (⅝ in.) diameter Grade 5 bolts 973 each. As seen in
The improved splice mechanism 970 maintains the advantages of the initial design 950, namely, requiring the mandrel to shear off only two bolts at one time, thus greatly reducing the energy and associated force level; and keeping the splice plates outside of the tubes so that they do not interfere with the mandrel. In addition, the improved design 950 provides much greater moment capacity to the splice mechanism, thus improving the performance of the barrier system for redirectional types of impacts.
Although the invention has been described with reference to a specific embodiment, this description is not meant to be construed in a limiting sense. On the contrary, various modifications of the disclosed embodiments will become apparent to those skilled in the art upon reference to the description of the invention. It is therefore contemplated that the appended claims will cover such modifications, alternatives, and equivalents that fall within the true spirit and scope of the invention.
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|U.S. Classification||188/377, 188/374, 293/133|
|International Classification||B60R, E01F15/14, B65B7/00, F16F7/12|
|Cooperative Classification||F16F7/125, E01F15/143|
|European Classification||E01F15/14C, F16F7/12F|
|Nov 13, 2006||AS||Assignment|
Owner name: SAFETY BY DESIGN CO., NEBRASKA
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:REID, JOHN D.;ROHDE, JOHN R.;SICKING, DEAN L.;REEL/FRAME:018592/0532
Effective date: 20061102
|Dec 21, 2009||FPAY||Fee payment|
Year of fee payment: 4
|Dec 12, 2013||FPAY||Fee payment|
Year of fee payment: 8